Pressure cooker with vertically shiftable cover and exhaust therefor



June 28, 1960 H. v. KELTON 2,942,753

- v PRESSURE COOKER WITH VERTICALLY SHIFTABLE covER AND EXHAUST THEREFOR7 Filed June 8, 1959 2 Sheets-Sheet 1 INVENTOR. A HEOAD 1 Kean-av BY zz-g fljf -g A rrqeus vs June 1960 H. v. KELTON 2,942,753

PRESSURE OKER WITH VERTIC LY SHIFTABLE CO ND EXHAUST TH FOR Filed June8, 1959 2 Sheets-Sheet 2 United States Patent 2,942,753 PRESSURE COOKERWITH VERTICALLY SHIFT- ABLE COVER AND EXHAUST THEREFOR Harold V. Kelton,South Beloit, Wis, assignor to Louis A. M. Phelan Filed June 8, 1959,Ser. No. 818,654

Claims. (Cl. 220-33) The present invention relates to high speedpressure cookers of the type in which the food to be processed isimmersed in a very hot, non-aqueous and non-toxic cooking fluid and acover of the cooking vessel is then lowered into the vessel for sealingtherewith and locked in position. A pressure is quickly built up withinthe vessel, preferably through the use of moisture behing injected intothe vessel.

Cooking devices of this type are large, often being on the order of 16inches in diameter, and as a superatmospheric pressure in the vessel of35 p.s.i. is commonplace, a considerable force acts on the cover tendingto open it during the cooking operation. Therefore, the cover must beeifectively sealed and securely locked in place during operation. Inaddition, the cooker should be incapable of being opened until thepressure has dropped to atmospheric in order to prevent any hot fat, ata usual temperature of 350 degrees F., from blowing out of the vessel.

Consequently, covers for these cookers are heavy, large, very hot andgenerally awkward to handle. On the other hand, speed and efliciency ofoperation are essential and, in quick-order eating establishments wherethese cookers find considerable utility; the cover must be opened andclosed quickly and many times during the day. The operation of thecooker must be as effortless, safe and foolproof as possible.

The present invention utilizes a horizontally swingably yoke forsupporting the cover, which cover is positively shiftable in eithervertical direction to open or close the vessel. This general type ofyoke is shown in the copending U.S. application Serial Number 605,872,filed August 23, 1956, and entitled Pressure Cooker, now Patent No.2,917,200 and by means of which subject matter-the operator can easilyand quickly open and close the cover by means of a lever operated cam.The arrangement is such that the cover cannot be opened until pressurein the vessel has been reduced to at least a predetermined value.

As previously mentioned, a non-toxic and non-aqueous cooking fat inthevessel is often brought up to a temperature of 350 degrees F., or evenhigher, depending on the type of food being cooked. Many cookingoperations are performed during the day in which a basket of food-isimmersed in this fatand, after a cooking period of a few minutes, iswithdrawn fromthe fat. As this fat is used, it becomes progressivelymore foamy in nature. In other words, as the fat gets older it bubblesand foams to such an extent that it must be discarded and replaced withnew, clean fat. The location of the exhaust port for such a cooker istherefore important because when the fat reaches such a condition thatit rises in, the vessel to level of the exhaust conduit, it will be lostwhen it passes through the conduit and require replacement. Furthermore,the fat will plug the conduit to prevent proper pressure releasetherethrough. It is therefore important to locate the exhaust port atthe maximum possible height in the vessel because when the cooking fatreaches this port it must be replaced with new cooking fat.

The above mentioned problems of the location of the exhaust port aredealt with in the'co-pending U.S. application Serial Number 705,190,filed December 26, 1957, and entitled Pressure Cooker, of which subjectmatter 2 I am a co-inventor. The subject matter of that application hasthe exhaust port located in the cover, which is highly desirable, butthe cover is mounted for swinging about a horizontal axis located at oneside of the vessel, which particular mounting has proven satisfactoryfor certain installations. With a cover so mounted about a horizontaland particularly located axis, a swivel joint connection was providedfor the exhaust between the cover and the rest of the cooker, whichconnection would always be in a coupled or exhaust-transmittingcondition.

One of the problems in using a vertically shiftable cover of the typeshown in said application Serial Num ber 605,872, now Patent No.2,917,200 and also utilized in the present invention, is in providing anexhaust port in the cover of the vessel and connecting the port with therest of the cooker. Such a connection must be coupled and uncoupledwithout any attention on the part of the operator and the use of aflexible connection for this purpose has not been acceptable due, interalia, to sanitary requirements and heat and pressure problems.

In accordance with the present invention there has been provided apressure cooker of the type having a truly vertically shiftable cover,which has an improved means for conducting exhaust from the cookerthrough the cover and directing it to a relatively stationary locameansof the above type in which a conduit extends from a portin the cover andis rigidly carried by the cover for both'vertical shifting and swingingmovement therewith. This conduit terminates in a downwardly extendingend which isprecisely aligned with its complementary socket 'on' theframe of the cooker when the cover; is' in vertical alignment with thevessel. rangement is such that when closing the cover, the cover must beactually commencing to enter the cylindrical sealing surface ofthevessel before the endof the exhaust conduit begins .to enter. itscomplementary stationary Figure 2 is a side elevational view, of thecooker in the closed position, partially in section and broken away,

and taken generally through the support yoke for the cover and alongline 22 of Figure 3; V l t .Figure 3 is a plan view of the cooker asshown in Figure 2 and showing a moved position of the cover and exhaustconduit in broken lines; a

Figure 4 'is an enlarged,'fragm entary,ldetail view of the cover when inthe sealing position; t

Figure 5 is a fragmentary sectional view taken generally along line 5'5.of Figure 3;

Figure 6'isuan enlarged detailview of a portion of Figure Sbut showingthe cover when it commences to edgage the internal-cylindrical sealingsnrfaceof the vessel,

and

Figure .7 is. a Figure 2.

Referring in' greater detail to the drawings, a sheet metal counter'top1 has a. circular opening thereindefined byan upwardly .turnedflange 2,in which is mounted the I cylindrical sheet metal vessel 3. An angleiron frame 4 rigidifies the counter top and supports the weight of thevesseL: The counter top isformed as a roundeorneri The ardetail viewtaken along the lii1e.7----7;in]

crossjsection in the "yoke :when the latter is in :theiclosed 1threadably engaged iri anchor blocksjiS l'andi29,' respectively. g a t jl a I zTh'us, -the covermay beverticallyzshifted withrespect tobothitssupporting yokefand 'tlre'jvess'el. 'alsorswingable together withthe wokeg a'nd the vessehgaboutits pivot column I2; :In accordancewith'thet-present inventlon,

along its front edge and islturned upwardly. at its rear edge toform aback wall '6;

:collar or sleevey7 snugly zsu'rroundsthelflangefisof theJcounter-topuand extends upwardlyiherefiom;

:T he vessel 3tispreferably tormed'of 'stainless s teel and 5 bya deepdraw fprocess. 'The bottom of the'vessel iterminatesin a sump '8 havinga -clean out val'vell at 'the lowermos't'end.

As previously mentioned, the cover '10 is mdunte'dton a horizontallyswin'gablylyoke'll which is hinged onipivot column '12 at onefside of.the vessel. On stheJopposite side of the vessel is secured-alockingicolumn 13 which has "ahead 14 that is engaged by theslot 15 ofiT-shaped position. 'The locking column 13 acts "as a guide for 15accuratelylocating the 'coverab'ove the vessel for engagement therein.The cover is forcibly-moved inueither' vertical position by the cam17*fixed to'the hand lever. 18.

t In this manner the cover is forcibly raised'above "the vessel to'thebpenuposit ion shown in'rFigure 1"01'. -fOl'Clbly 20 lowered to theclosed position within the vessel, zassshown in Figures 2 to 5inclusive.

The upper'internal cylindrical surface fltll'of the-vessel is thesealingarea againstwhich. is compressed the'O-ring 21 carried in thegro'ove22-oftheQcOveLi'F-Ihis surface is of a very'smooth finish so? as toprevent wear of the -'O-ring and insure-positive sealing thereby. .AstheO-ring is slid 'over this surface many times, a propersealing'relationship between area zo a'ndfthe n'ingt-mustbejprovideidfor good lifeof theiO-r-ing."

'7 'With' this sealing arrangement, oncethe :O-ring has .en-t

gaged the cylindrical sealing "surface 20, "'ifjS in :a position toefiect a seal and pressure canimmediatelybe built up'within the vessel.Stated otherwi'sejthe ao-rin'grcan provide the scaling functionregardless-of its precise-Pvertical position along'the sealing surface.Therefore; as

soon as the'O-ring moves downwardly past the rounded corner 23 of thevessel it begin'sits'sealing functiom' The rounded -cornerj23 acts.tojtcompress r the'to-ring "initially,

to-facilitate entry-ofithe cover'into thevessel.

:?It :is essenti'al, with such a sealing arrangem'englthatthe'concentricity of the "upper end of the vessel be'h'ia-intainedlprecisely so that the cover can move treelytherein and at the same timeinsuretthat aproper sealingzaction occurs. A means for providing thisconcentricityand alignment between thefcover, vessel and thet'other'associated parts, is shown and described inthe-said application'SerialNumber 605,872, now Patent No. 2,917,200,

and takes the form of a'ring which is'shrink-fi'tted around the upperportion of the vessel. Thatring'also act'stas 'a a 7 guide foraccurately locating the side columns whichsup a port the cover.lf-aimore detailed description fofi'th-is sealing action, or the camoperated leverforrshifting ithe cover is deemednecessary or desirable;reference may a be had to thatapplication; In regardto'thelatterifeature, i

it-is believed suflicient to saythat' the cam- 17 hasa bore 174:;(Eiga5)into which-the rod'24tof thepi ton 24aex-" tendswhen pressure aboveapredeterminedfamountexists in the vessel, thus preventing openingdflthelcover'. f I Ini the present'casejanoutwaIdlyiturned fiang' 25*isformed integrally with the" vessel and 3f the i; same time that thedeepj drawn procesSjofttheivessel 'iakes'placer 'A.-downwardly turnedflange51261is also iormd siniultaneously --ar Q ln drthe 'outeiiedge ofthe thorizohtal flange; 25. The 've'ssel' rests on the: sleeve *7byi'pitsffiange '25; Columns 12 and 13 extend through flange 25 and" area (represented by? line and tea stationary sockett located preferablyadjacent to the cover when the latter in the closed position.

As shown in Figure :5, a port 30 is provided in the cover whichterminates in the upper side thereof; A conduit fitting 3 1; is secured;byi bolts 32 iin communication with the port. The upper portion ot'thisfitting carries a conventional pressure relief valve 33, which valvecould also be located elsewhere in the cover, if desired. The conduitfitting extends hor-izontally and :then downwardly where it terminatesin aii intenengaging portion in the 'formof a free end 34 having asealing .O-ring 35 there- 7 around. Thearrangement isisuch that the freeend terminates over the flangewhen the .cover is in the closedposition.' i r a .v 7 i More particularly,'the'free end is 'alignablewith aicomplementary inter-'engaging i'member :tinnthe form of a socketfitting 37 which extends :throughlflange -2.5 andis held captive thereinby the anchor block 38 located :beneath the flange and with which blockitiis threadably engaged. 9

The upper-end of thejtubularu' socket member 31 has an internal chamfer39 which acts to initially-compress 'the O-ring 35 upon entering thebore of the fitting .37.

A pipe 40 isxthreadablyrengaged with 'thelower end of member 37 andserves to conduct the exhaust material to a collectingpail, or theilike(not-shown); located :in the bottom of the cabinet.

Instead'of thelformvofr .constructionshownz-for illustrative purposes,the socket member'may be located on the freeend of the conduit fittingwand the-male :interengaging portion withits O=ring seal could besecured ;to

or adjacentto vessel flange. a

' vThe cover, due to its largelsize andconstructionrand also due to the'fact that it v-ismounted directly nndenthe cam, Inot be ';damaged if itis inadvertently :closed downagainst theifiange 25iof'thelyessel.Furthermore,-

the cover is aligned'withthe vessel'bymeans'of 'therlocking'fcolumn13fiand slot .15-onthe yoke and guided into the upperend of the vessel.

As the cover is moved downwardly bythe cam,'the cover enters thepot'andis positioned :in the cylindrical sealing surfacet20 as soonasitpassesthe lowe'r roun'ded corner 23. This'is the position shownin Figure'6 at which time the lower end 34 of the exhaust conduit :is

still clear of the socket member 37; Therefore; :the'conduitFend 34' isprecisely alignedwithiitslsocket, by the guiding action of the eoverandvessel, before/it engages the socket. As a result; bending orother'damage to the relatively weak and oflf-center conduit manifoldfitting due to improper striking the socketmember, isrpreventecl.

This is accomplished by makinglthe'dis'tancefifrom the bottom end 34 ofthe exhaust-to thexbottom of'thecover (represented by 'theiline AB:)greater ftha'nthe distance from the .top of the'-socket;member137 'tothezupprzextreme end of the internal cylindrical surface' ot thevesselFurtherr'nore, as'show'n 1 should be greater tha'nfthet dlstahce' snfthe socke't mernber -37 extends above Ithe flange, and

' precludestai designfin whichfa recessionfiitting the ex-f haust-islocated below flange25. g

ith the 1 above construction and parts, problems duejto'small errors iniswinging the-cover completely fjandiprecisely into alignment with; thevessel, t or due'to side play inthe support-mechanismhavebeen overcome;the radius;23 on the upperfend of the-vessel guides the" icover into*thetproper' 'sealing :position as sits sealing edge is lowered-aridbfdfethe hdmf tthe exhaust conduit homes down to 'the level df the -topof' -the socket member. 37. Thus the exhaust conduit is always inaligndimensioning of the ment with its socket upon entering the latterand cannot be damaged by improper contact therewith.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

What is claimed and desired to be secured by Letter Patent is:

1. In a pressure cooker, the combination comprising, a vessel having aninternal cylindrical sealing surface which defines an open top, a coverhaving a sealing edge around its periphery, said cover being mounted forvertical shifting between an open position in which it is located abovethe vessel and a closed position in which its sealing edge engages saidsealing surface, said cover also being mounted for horizontal swingingrelative to said vessel between a position aligned directly above saidvessel and a position to one side thereof, a rigid exhaust conduitsecured to said cover and extending outwardly therefrom and terminatingin a generally downward extending intereugaging portion, and acomplementary interengaging member mounted on said cooker andterminating in an open upper end so as to engage and be in fluidreceiving communication with said interengaging portion when said coveris moved downwardly into said vessel.

2. A device as defined in claim 1 further characterized in that whensaid cover is closed, the vertical distance from the lowermost portionof said sealing edge is less to the top of the vessel than it is to thebottom of said interengaging portion.

3. A pressure cooker comprising, a cylindrical vessel having an internalcylindrical sealing surface which defines an open top, a cover havingseal means around its periphery, said cover being mounted for verticalshifting between an open position in which it is located above thevessel and a closed position in which its seal means engages saidsealing surface, said cover also being mounted for horizontal swingingrelative to said vessel between a position aligned directly above saidvessel and a position to one side thereof, an exhaust port extendingthrough the top of said cover, an exhaust conduit rigidly fastened tosaid cover in communication with said port and extending outwardly fromsaid cover and terminating in a downwardly extending free end, and astationary socket member mounted on said cooker and adjacent said vesseland terminating in an open upper end, said upper end being adapted tosealingly receive said conduit free end when said cover is moveddownwardly into engagement with said sealing surface.

4. In a pressure cooker, the combination comprising, a vessel having aninternal cylindrical sealing surface which defines an open top, a coverhaving a sealing edge mounted for vertical shifting between an openposition in which it is located above the vessel and a closed positionin which it engages said sealing surface, said cover also being mountedfor horizontal swinging relative to said vessel between a positionaligned directly above said vessel and a position to one side thereof, arigid exhaust conduit fastened to said cover and extending outwardlytherefrom and terminating in a generally downward extending free end,and a stationary socket on said cooker and terminating in an open upperend, said upper end being adapted to receive said conduit free end whensaid cover is being moved downwardly into said vessel, the verticaldistance between the lowermost portions of said sealing edge and saidfree end being greater than the vertical distance between the uppermostportions of said cylindrical sealing surface and said socket upper end.

5. A device as defined in claim 4 further characterized in that thevertical distance from the lowermost portion of said sealing edge isless to the top of the vessel than it is to said conduit free end.

6. In a cylindrical pressure cooker vessel having an open top, ahorizontally swingable support pivotally mounted at one side of thevessel, a cover slidably mounted on said support and in a verticaldirection in respect thereto, said cover adapted to slide downwardlyinto said vessel for sealing thereof and slide upwardly above saidvessel for opening the latter, said support and said cover swingabletogether in a horizontal direction between a position at one side ofsaid vessel and an aligned position directly above said vessel, theimprovement comprising, an exhaust conduit mounted on said cover andextending outwardly therefrom and terminating in a generally downwardextending free end, and a stationary socket mouted adjacent said vesseland having an upwardly facing upper end with which said free end isadapted to be sealingly coupled, said socket upper end and said conduitfree end being in precise vertical alignment but uncoupled from oneanother when said cover commences to enter said vessel.

7. A device as set forth in claim 6 further characterized in that thevertical distance from a lowermost portion of said sealing edge is lessto the top of the vessel than it is to said free end.

8. In a cylindrical pressure cooker vessel having an open top, ahorizontally swingable support means pivotally mounted at one side ofthe vessel, a cover slidably mounted on said support means and in avertical direction in respect thereto, said cover having a sealing edgewhich is adapted to slide downwardly into said vessel for sealingthereof and slide upwardly above said vessel for opening the latter,said support means and said cover swingable together in a horizontaldirection between a position at one side of said vessel and an alignedposition directly above said vessel, the improvement comprising, anexhaust conduit mounted on said cover and extending outwardly therefromand terminating in a generally downward extending free end, and astationary socket mounted adjacent said vessel and having an upwardlyfacing upper end with which said free end is adapted to be sealinglycoupled, said socket upper end and said conduit free end being inprecise vertical alignment from one another when said cover commences toenter said vessel, the arrangement and relative dimensions of the partsbeing such that the vertical distance between the lowermost portions ofsaid sealing edge and said free end is greater than the distance betweenthe uppermost portions of said cylindrical sealing surface and saidsocket upper end.

9. A device as set out in claim 8 wherein the vertical distance from alowermost portion of said sealing edge is less to the top of the vesselthan it is to said conduit free end.

10. In a pressure cooker, the combination comprising, a vessel having anintegrally formed and outwardly flared flange at its upper end, saidvessel also having an internal cylindrical sealing surface adjacent saidflange and which defines an open top, a cover having a sealing edgearound its periphery, said cover being mounted for vertical shiftingbetween an open position in which it is located above the vessel and aclosed position in which its sealing edge engages said sealing surface,said cover also being mounted for horizontal swinging relative to saidvessel between a position aligned directly above said vessel and aposition to one side thereof, a rigid exhaust conduit secured to saidcover and extending outwardly therefrom and terminating in a generallydownward extending free end, and a socket member mounted on said flangeand terminating in an open upper end, said upper end being adapted toreceive said conduit free end when said cover is being moved downwardlyinto said vessel.

References Cited in the file of this patent UNlTED STATES PATENTS893,808 Napier July 21, 1908 1,070,128 Gross Aug. 12, 1913 1,545,352Rodriguez July 7, 1925 1,892,587 Schmieg Dec. 27, 1932 2,120,961 BeedeJune 21, 1938 2,917,200 Phelan et a1 Dec. 15, 1959

